The fabrication of porous semiconductor body regions is known. By way of example, the production of a porous semiconductor body region by means of anodic oxidation has been shown. In this case, the porous semiconductor body region is fabricated by means of anodic oxidation of the semiconductor body from the rear of the semiconductor body into the semiconductor body.
It is desirable to provide a method for fabricating a locally bounded porous semiconductor body region deep in the semiconductor body. Furthermore, it is desirable to provide a method for fabricating a deep foreign substance region using a porous semiconductor body region.